From the 1990s the research interests and efforts to study the third sector have increased rapidly. The research has proceeded by approaching the third sector from different perspectives and frameworks related to several scientific disciplines and policy areas. While the societal importance and visibility of third sector organizations has grown quickly, the third sector has become a quite diverse and diffuse field of studies (Anheier et al. 2002). The variety of perspectives and themes is well visible also in the contents of this book. This chapter looks at the contents as a whole with a general glance.